OS/2

from Jargon File (4.4.4, 14 Aug 2003)

OS/2
 /O S too/, n.

   The anointed successor to MS-DOS for Intel 286- and 386-based micros;
   proof that IBM/Microsoft couldn't get it right the second time,
   either. Often called `Half-an-OS'. Mentioning it is usually good for a
   cheap laugh among hackers -- the design was so {baroque}, and the
   implementation of 1.x so bad, that three years after introduction you
   could still count the major {app}s shipping for it on the fingers of
   two hands -- in unary. The 2.x versions were said to have improved
   somewhat, and informed hackers rated them superior to Microsoft
   Windows (an endorsement which, however, could easily be construed as
   damning with faint praise). In the mid-1990s IBM put OS/2 on life
   support, refraining from killing it outright purely for internal
   political reasons; by 1999 the success of {Linux} had effectively
   ended any possibility of a renaissance. See {monstrosity},
   {cretinous}, {second-system effect}.

from The Free On-line Dictionary of Computing (8 July 2008)

OS/2
Merlin
Warp

   /O S too/ {IBM} and {Microsoft}'s successor to the {MS-DOS}
   {operating system} for {Intel 80286} and {Intel 80386}-based
   {microprocessors}.  It is proof that they couldn't get it
   right the second time either.  Often called "Half-an-OS".  The
   design was so {baroque}, and the implementation of 1.x so bad,
   that 3 years after introduction you could still count the
   major {application programs} shipping for it on the fingers of
   two hands, in {unary}.  Later versions improved somewhat, and
   informed hackers now rate them superior to {Microsoft
   Windows}, which isn't saying much.  See {second-system
   effect}.

   On an {Intel 80386} or better, OS/2 can {multitask} between
   existing {MS-DOS} {applications}.  OS/2 is strong on
   connectivity and the provision of robust {virtual machines}.
   It can support {Microsoft Windows} programs in addition to its
   own {native} applications.  It also supports the {Presentation
   Manager} {graphical user interface}.

   {OS/2} supports {hybrid multiprocessing} (HMP), which provides
   some elements of {symmetric multiprocessing} (SMP), using
   add-on IBM software called {MP/2}.  OS/2 SMP was planned for
   release in late 1993.

   After OS/2 1.x the {IBM} and {Microsoft} partnership split.
   IBM continued to develop OS/2 2.0, while Microsoft developed
   what was originally intended to be OS/2 3.0 into {Windows NT}.
   In October 1994, IBM released version OS/2 3.0 (known as
   "Warp") but it is only distantly related to {Windows NT}.
   This version raised the limit on RAM from 16MB to 1GB (like
   Windows NT).

   IBM introduced networking with "OS/2 Warp Connect", the first
   multi-user version.  OS/2 Warp 4.0 ("Merlin") is a {network
   operating system}.

   (http://mit.edu:8001/activities/os2/os2world.html).

   [Dates?]

   [{Jargon File}]

   (1995-07-20)